1. Field of the Invention
The invention relates to firearm safety devices.
2. Description of the Related Art
The need for providing a reliable, low cost safety device for firearms has long been recognized. A vast number of solutions have been proposed. Trigger locks, locking cabinets, safety plugs are a few of the many types of proposed devices.
While many of the devices proposed ensure that the firearm cannot be fired, these devices are impractical for businesses which engage in selling firearms. In order to sell the firearms, reasonable access must be available to the general public to test the actions, inspect the barrels, etc. However, it is inherently easy for a deranged person to surreptitiously load the firearm during this inspection process with the expectation that the next test by someone else will result in an accidental discharge.
Therefore, firearms must be readily available for inspection and testing yet inherently safe from having a live round being loaded. Trigger locks and other similar devices do not enable the firearm to be tested. Removal of the lock for testing destroys the effectiveness of the safety. Rods which lock into the barrel again interfere with the customer's ability to inspect the firearm. Further, such devices are too expensive to be used for each firearm within the store.
Another safety problem results from the use of semi-automatic weapons for police work. Most police forces today have switched to the use of semi-automatic handguns, in particular, 9 mm caliber. When the police officer returns home at the end of his/her shift, it is customary to unload the weapon and remove the clip. While it is easy to visually inspect whether the clip is removed, the presence or absence of a round in the chamber cannot be determined without activating the slide to open the action. It would be advantageous to be able to visually confirm that the weapon was unloaded. It would also be advantageous to provide a visual reminder to prompt the officer to reload the weapon before returning to duty.
Revolvers present a more challenging problem. Since a revolver has multiple firing chambers in the cylinder, access to the cylinder itself must be disabled to prevent a cartridge from being maliciously or inadvertently loaded.
U.S. Pat. No. 4,776,123, issued to Ascroft on Oct. 11, 1988, discloses a safety plug for firearm chambers that is incapable of being ejected by the firearm's cartridge extractor mechanism. The device is press fitted in the bore of the firearm by having a diameter greater than the bore of the weapon. To fit properly requires the diameter of the plug to be precisely determined relative to the barrel bore. Variations in wear of the bore or deposits within would require corresponding adjustments in the plug diameter. As a pressure fit has small surface area of contact between the plug and the firearm, jarring the firearm could cause the safety plug to drop out.
U.S. Pat. No. 3,444,639, issued to Rockwood on May 20, 1969, discloses another safety plug for firearm chambers. This design is capable of being ejected by the firearm extractor mechanism. Therefore, anyone can disable the safety device simply by ejecting the plug.
U.S. Pat. No. 3,848,350, issued to Seminiano on Nov. 19, 1974, discloses still another plug. The primary objective of this device is to serve as a "dry fire" plug for center-fire or shotguns. Again, this plug can be ejected using the firearm extractor mechanism.
U.S. Pat. No. 3,678,609, issued to Fazio on Jul. 25, 1972, discloses still another safety plug. This device is friction fitted within the firing chamber by having the outer diameter of the plug being slightly greater than the diameter of the firing chamber.
Another "dry fire" plug design for shotguns being sold by the L. L. Bean Co., of Freeport, Me., features an O-ring set within a groove that locates the device within the firing chamber of the shotgun. The O-ring is snugly fit within the groove and is designed for a loose fit so that the plug can be ejected using the firearm extractor mechanism.
None of these devices is suitable to economically solve the safety problems described above.